Method and device for obtaining stearin from animal or vegetable fats

Abstract

1. Method and Apparatus for the production of stearin from fat of animal or plant origin. 2.1 A method is carried out such that during the duration of a production run, a sharp separation between the stearin phase and the oil phase is maintained at a constant rate, to achieve an optimum quality of stearin and stearin yield. 2.2. Crystallized oil of a temperature from 10 C to 40 C is fed into inlet ( 12 ) of a nozzle-type centrifuge ( 11 ) which is not self-emptying and is equipped with a stack of plates ( 15 ) and a stationary gripping device ( 16 ) for the oil phase. The solid phase is guided through flow chambers tapering towards the nozzles ( 20 ) and discharged through these nozzles. To realize a high degree of separation between the stearin phase and the oil phase, the ratio between the feed rate in I/h and the nozzle capacity in I/h is adjusted in the range between 2:1 and 4:1. 2.3 The method is used for stearin production from animal or plant fats. 3. FIG. 2.

What is claimed is:  
     
       1. A method for obtaining crystallized solid phases from fat of animal or plant origin, comprising the steps of: 
       heating fat to a temperature until liquefied to form a liquid free of crystals;  
       cooling the liquid step-by-step to a temperature in the temperature range from 40° C. to above 10° C. to obtain a crystallized oil;  
       introducing the crystallized oil into a non-self-emptying nozzle-type centrifuge for separating a solid phase; and  
       conducting the solid phase through flow chambers tapering towards nozzles of the centrifuge for discharge through the nozzles.  
     
     
       2. The method of claim  1  wherein the cooling step is carried out in a first phase at a temperature differential of 15° C. between the liquid and a heat-exchange medium, and in a second phase to a temperature between 40° C. and above 10° C. at a temperature differential of 3° C. between the liquid and the heat-exchange medium. 
     
     
       3. The method of claim  2  wherein the liquid is cooled down during the second cooling phase to a temperature of 36° C. over a period of 420 minutes. 
     
     
       4. The method of claim  2  wherein the liquid is agitated during the first cooling step at 8 rpm and during the second cooling phase at 4 rpm. 
     
     
       5. The method of claim  3  wherein the heat exchange medium is water. 
     
     
       6. The method of claim  1 , wherein the solid phase is conducted through the flow chambers with the ratio of an input rate in liters per hour incoming crystallized oil to a nozzle output rate in liters per hour being adjusted in a range between 2:1 and 4:1. 
     
     
       7. The method of claim  1 , wherein the crystallized solid phase obtained is stearin. 
     
     
       8. Apparatus for producing stearin from fat of animal or plant origin, comprising: 
       a crystallizer for heating fat and subsequently cooling the fat step-by-step to obtain a crystallized oil;  
       a non-self-emptying centrifuge positioned downstream of the crystallizer and including a centrifuging drum having accommodated therein a stack of plates for separating a solid phase from the crystallized oil, and nozzles formed circumferentially about the centrifuging drum, said solid phase being guided via flow chambers to the nozzles for discharge, with the flow chambers being so bounded by inserted segments as to taper towards the nozzles, with the ratio of an input rate in liters per hour of incoming crystallized oil to a nozzle output rate in liters per hour being adjusted in a range between 2:1 and 4:1.  
     
     
       9. The apparatus of claim  8  wherein the segments provided in the centrifuging drum are made of stainless steel. 
     
     
       10. The apparatus of claim  9  wherein the segments extend from an outer area of the stack of plates to the nozzles. 
     
     
       11. The apparatus according to claim  8  wherein the nozzles have a nozzle mouth at a diameter of about 0.5 mm or about 0.6 mm.